Non-volatile memory (NVM) devices are memory devices that retain or store data even when power is off. Non-volatile memory devices, for example, include flash devices which can be programmed using electrical signals. It is desirable to embed NVM devices with logic devices, such as metal-oxide semiconductor (MOS) devices, to form embedded NVM (eNVM) devices. Conventional eNVM devices have various issues, such as different gate heights between NVM cells and logic devices. The different gate heights create processing complexity in forming eNVM devices. For example, different gate heights create problems in forming contact landings. In addition, logic devices, such as high voltage MOS (HVMOS) devices, are incompatible with silicon-on-insulator (SOI) substrates due to intrinsic floating body effect, negatively impacting the performance of the devices.
The present disclosure is directed to providing reliable and high performing eNVM devices which can be easily manufactured.